diff --git a/UpdateEngine.conf b/UpdateEngine.conf
index 58cca09..192e6ab 100644
--- a/UpdateEngine.conf
+++ b/UpdateEngine.conf
@@ -53,6 +53,9 @@
            send_member="SetUpdateOverCellularPermission"/>
     <allow send_destination="org.chromium.UpdateEngine"
            send_interface="org.chromium.UpdateEngineInterface"
+           send_member="SetUpdateOverCellularTarget"/>
+    <allow send_destination="org.chromium.UpdateEngine"
+           send_interface="org.chromium.UpdateEngineInterface"
            send_member="GetUpdateOverCellularPermission"/>
     <allow send_destination="org.chromium.UpdateEngine"
            send_interface="org.chromium.UpdateEngineInterface"
diff --git a/binder_bindings/android/brillo/IUpdateEngine.aidl b/binder_bindings/android/brillo/IUpdateEngine.aidl
index b1a1b4f..7893548 100644
--- a/binder_bindings/android/brillo/IUpdateEngine.aidl
+++ b/binder_bindings/android/brillo/IUpdateEngine.aidl
@@ -33,6 +33,8 @@
   void SetP2PUpdatePermission(in boolean enabled);
   boolean GetP2PUpdatePermission();
   void SetUpdateOverCellularPermission(in boolean enabled);
+  void SetUpdateOverCellularTarget(in String target_version,
+                                   in long target_size);
   boolean GetUpdateOverCellularPermission();
   long GetDurationSinceUpdate();
   String GetPrevVersion();
diff --git a/client_library/include/update_engine/update_status.h b/client_library/include/update_engine/update_status.h
index 3e9af5b..2f6322a 100644
--- a/client_library/include/update_engine/update_status.h
+++ b/client_library/include/update_engine/update_status.h
@@ -23,6 +23,9 @@
   IDLE = 0,
   CHECKING_FOR_UPDATE,
   UPDATE_AVAILABLE,
+  // Broadcast this state when an update aborts because user preferences does
+  // not allow update over cellular.
+  NEED_PERMISSION_TO_UPDATE,
   DOWNLOADING,
   VERIFYING,
   FINALIZING,
diff --git a/common/constants.cc b/common/constants.cc
index c0bb874..1bb4058 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -79,6 +79,10 @@
 const char kPrefsUpdateFirstSeenAt[] = "update-first-seen-at";
 const char kPrefsUpdateOverCellularPermission[] =
     "update-over-cellular-permission";
+const char kPrefsUpdateOverCellularTargetVersion[] =
+    "update-over-cellular-target-version";
+const char kPrefsUpdateOverCellularTargetSize[] =
+    "update-over-cellular-target-size";
 const char kPrefsUpdateServerCertificate[] = "update-server-cert";
 const char kPrefsUpdateStateNextDataLength[] = "update-state-next-data-length";
 const char kPrefsUpdateStateNextDataOffset[] = "update-state-next-data-offset";
diff --git a/common/constants.h b/common/constants.h
index 660d9a9..208755d 100644
--- a/common/constants.h
+++ b/common/constants.h
@@ -82,6 +82,8 @@
 extern const char kPrefsUpdateDurationUptime[];
 extern const char kPrefsUpdateFirstSeenAt[];
 extern const char kPrefsUpdateOverCellularPermission[];
+extern const char kPrefsUpdateOverCellularTargetVersion[];
+extern const char kPrefsUpdateOverCellularTargetSize[];
 extern const char kPrefsUpdateServerCertificate[];
 extern const char kPrefsUpdateStateNextDataLength[];
 extern const char kPrefsUpdateStateNextDataOffset[];
diff --git a/common/error_code.h b/common/error_code.h
index e08ec46..bcf541c 100644
--- a/common/error_code.h
+++ b/common/error_code.h
@@ -73,6 +73,7 @@
   kFilesystemVerifierError = 47,
   kUserCanceled = 48,
   kNonCriticalUpdateInOOBE = 49,
+  kOmahaUpdateIgnoredOverCellular = 50,
 
   // VERY IMPORTANT! When adding new error codes:
   //
diff --git a/common/error_code_utils.cc b/common/error_code_utils.cc
index ad4aeeb..0169ab8 100644
--- a/common/error_code_utils.cc
+++ b/common/error_code_utils.cc
@@ -144,6 +144,8 @@
       return "ErrorCode::kUserCanceled";
     case ErrorCode::kNonCriticalUpdateInOOBE:
       return "ErrorCode::kNonCriticalUpdateInOOBE";
+    case ErrorCode::kOmahaUpdateIgnoredOverCellular:
+      return "ErrorCode::kOmahaUpdateIgnoredOverCellular";
     // Don't add a default case to let the compiler warn about newly added
     // error codes which should be added here.
   }
diff --git a/common_service.cc b/common_service.cc
index 20f55ab..b8bc298 100644
--- a/common_service.cc
+++ b/common_service.cc
@@ -16,7 +16,6 @@
 
 #include "update_engine/common_service.h"
 
-#include <set>
 #include <string>
 
 #include <base/location.h>
@@ -41,7 +40,6 @@
 using base::StringPrintf;
 using brillo::ErrorPtr;
 using brillo::string_utils::ToString;
-using std::set;
 using std::string;
 
 namespace chromeos_update_engine {
@@ -250,24 +248,12 @@
 
 bool UpdateEngineService::SetUpdateOverCellularPermission(ErrorPtr* error,
                                                           bool in_allowed) {
-  set<string> allowed_types;
-  const policy::DevicePolicy* device_policy = system_state_->device_policy();
-
-  // The device_policy is loaded in a lazy way before an update check. Load it
-  // now from the libbrillo cache if it wasn't already loaded.
-  if (!device_policy) {
-    UpdateAttempter* update_attempter = system_state_->update_attempter();
-    if (update_attempter) {
-      update_attempter->RefreshDevicePolicy();
-      device_policy = system_state_->device_policy();
-    }
-  }
+  ConnectionManagerInterface* connection_manager =
+      system_state_->connection_manager();
 
   // Check if this setting is allowed by the device policy.
-  if (device_policy &&
-      device_policy->GetAllowedConnectionTypesForUpdate(&allowed_types)) {
-    LogAndSetError(error,
-                   FROM_HERE,
+  if (connection_manager->IsAllowedConnectionTypesForUpdateSet()) {
+    LogAndSetError(error, FROM_HERE,
                    "Ignoring the update over cellular setting since there's "
                    "a device policy enforcing this setting.");
     return false;
@@ -278,9 +264,9 @@
 
   PrefsInterface* prefs = system_state_->prefs();
 
-  if (!prefs->SetBoolean(kPrefsUpdateOverCellularPermission, in_allowed)) {
-    LogAndSetError(error,
-                   FROM_HERE,
+  if (!prefs ||
+      !prefs->SetBoolean(kPrefsUpdateOverCellularPermission, in_allowed)) {
+    LogAndSetError(error, FROM_HERE,
                    string("Error setting the update over cellular to ") +
                        (in_allowed ? "true" : "false"));
     return false;
@@ -288,25 +274,63 @@
   return true;
 }
 
-bool UpdateEngineService::GetUpdateOverCellularPermission(ErrorPtr* /* error */,
-                                                          bool* out_allowed) {
-  ConnectionManagerInterface* cm = system_state_->connection_manager();
+bool UpdateEngineService::SetUpdateOverCellularTarget(
+    brillo::ErrorPtr* error, const std::string &target_version,
+    int64_t target_size) {
+  ConnectionManagerInterface* connection_manager =
+      system_state_->connection_manager();
 
-  // The device_policy is loaded in a lazy way before an update check and is
-  // used to determine if an update is allowed over cellular. Load the device
-  // policy now from the libbrillo cache if it wasn't already loaded.
-  if (!system_state_->device_policy()) {
-    UpdateAttempter* update_attempter = system_state_->update_attempter();
-    if (update_attempter)
-      update_attempter->RefreshDevicePolicy();
+  // Check if this setting is allowed by the device policy.
+  if (connection_manager->IsAllowedConnectionTypesForUpdateSet()) {
+    LogAndSetError(error, FROM_HERE,
+                   "Ignoring the update over cellular setting since there's "
+                   "a device policy enforcing this setting.");
+    return false;
   }
 
-  // Return the current setting based on the same logic used while checking for
-  // updates. A log message could be printed as the result of this test.
-  LOG(INFO) << "Checking if updates over cellular networks are allowed:";
-  *out_allowed = cm->IsUpdateAllowedOver(
-      chromeos_update_engine::NetworkConnectionType::kCellular,
-      chromeos_update_engine::NetworkTethering::kUnknown);
+  // If the policy wasn't loaded yet, then it is still OK to change the local
+  // setting because the policy will be checked again during the update check.
+
+  PrefsInterface* prefs = system_state_->prefs();
+
+  if (!prefs ||
+      !prefs->SetString(kPrefsUpdateOverCellularTargetVersion,
+                        target_version) ||
+      !prefs->SetInt64(kPrefsUpdateOverCellularTargetSize, target_size)) {
+    LogAndSetError(error, FROM_HERE,
+                   "Error setting the target for update over cellular.");
+    return false;
+  }
+  return true;
+}
+
+bool UpdateEngineService::GetUpdateOverCellularPermission(ErrorPtr* error,
+                                                          bool* out_allowed) {
+  ConnectionManagerInterface* connection_manager =
+      system_state_->connection_manager();
+
+  if (connection_manager->IsAllowedConnectionTypesForUpdateSet()) {
+    // We have device policy, so ignore the user preferences.
+    *out_allowed = connection_manager->IsUpdateAllowedOver(
+        NetworkConnectionType::kCellular, NetworkTethering::kUnknown);
+  } else {
+    PrefsInterface* prefs = system_state_->prefs();
+
+    if (!prefs || !prefs->Exists(kPrefsUpdateOverCellularPermission)) {
+      // Update is not allowed as user preference is not set or not available.
+      *out_allowed = false;
+      return true;
+    }
+
+    bool is_allowed;
+
+    if (!prefs->GetBoolean(kPrefsUpdateOverCellularPermission, &is_allowed)) {
+      LogAndSetError(error, FROM_HERE,
+                     "Error getting the update over cellular preference.");
+      return false;
+    }
+    *out_allowed = is_allowed;
+  }
   return true;
 }
 
diff --git a/common_service.h b/common_service.h
index 69368fb..4320d09 100644
--- a/common_service.h
+++ b/common_service.h
@@ -115,6 +115,12 @@
   bool SetUpdateOverCellularPermission(brillo::ErrorPtr* error,
                                        bool in_allowed);
 
+  // If there's no device policy installed, sets the update over cellular
+  // target. Otherwise, this method returns with an error.
+  bool SetUpdateOverCellularTarget(brillo::ErrorPtr* error,
+                                   const std::string& target_version,
+                                   int64_t target_size);
+
   // Returns the current value of the update over cellular network setting,
   // either forced by the device policy if the device is enrolled or the current
   // user preference otherwise.
diff --git a/connection_manager.cc b/connection_manager.cc
index 778cba5..47bd776 100644
--- a/connection_manager.cc
+++ b/connection_manager.cc
@@ -28,6 +28,7 @@
 #include "update_engine/common/prefs.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/system_state.h"
+#include "update_engine/update_attempter.h"
 
 using org::chromium::flimflam::ManagerProxyInterface;
 using org::chromium::flimflam::ServiceProxyInterface;
@@ -79,15 +80,23 @@
 
     case NetworkConnectionType::kCellular: {
       set<string> allowed_types;
+
       const policy::DevicePolicy* device_policy =
           system_state_->device_policy();
 
-      // A device_policy is loaded in a lazy way right before an update check,
-      // so the device_policy should be already loaded at this point. If it's
-      // not, return a safe value for this setting.
+      // The device_policy is loaded in a lazy way before an update check. Load
+      // it now from the libbrillo cache if it wasn't already loaded.
       if (!device_policy) {
-        LOG(INFO) << "Disabling updates over cellular networks as there's no "
-                     "device policy loaded yet.";
+        UpdateAttempter* update_attempter = system_state_->update_attempter();
+        if (update_attempter) {
+          update_attempter->RefreshDevicePolicy();
+          device_policy = system_state_->device_policy();
+        }
+      }
+
+      if (!device_policy) {
+        LOG(INFO) << "Disabling updates over cellular as device policy "
+                     "fails to be loaded.";
         return false;
       }
 
@@ -95,38 +104,17 @@
         // The update setting is enforced by the device policy.
 
         if (!ContainsKey(allowed_types, shill::kTypeCellular)) {
-          LOG(INFO) << "Disabling updates over cellular connection as it's not "
-                       "allowed in the device policy.";
+          LOG(INFO) << "Disabling updates over cellular per device policy.";
           return false;
         }
 
         LOG(INFO) << "Allowing updates over cellular per device policy.";
-        return true;
-      } else {
-        // There's no update setting in the device policy, using the local user
-        // setting.
-        PrefsInterface* prefs = system_state_->prefs();
-
-        if (!prefs || !prefs->Exists(kPrefsUpdateOverCellularPermission)) {
-          LOG(INFO) << "Disabling updates over cellular connection as there's "
-                       "no device policy setting nor user preference present.";
-          return false;
-        }
-
-        bool stored_value;
-        if (!prefs->GetBoolean(kPrefsUpdateOverCellularPermission,
-                               &stored_value)) {
-          return false;
-        }
-
-        if (!stored_value) {
-          LOG(INFO) << "Disabling updates over cellular connection per user "
-                       "setting.";
-          return false;
-        }
-        LOG(INFO) << "Allowing updates over cellular per user setting.";
-        return true;
       }
+
+      // If there's no update setting in the device policy, we do not check
+      // the local user setting here, which should be checked by
+      // |OmahaRequestAction| during checking for update.
+      return true;
     }
 
     default:
@@ -141,6 +129,22 @@
   }
 }
 
+bool ConnectionManager::IsAllowedConnectionTypesForUpdateSet() const {
+  const policy::DevicePolicy* device_policy = system_state_->device_policy();
+  if (!device_policy) {
+    LOG(INFO) << "There's no device policy loaded yet.";
+    return false;
+  }
+
+  set<string> allowed_types;
+  if (!device_policy->GetAllowedConnectionTypesForUpdate(
+      &allowed_types)) {
+    return false;
+  }
+
+  return true;
+}
+
 // static
 const char* ConnectionManager::StringForConnectionType(
     NetworkConnectionType type) {
diff --git a/connection_manager.h b/connection_manager.h
index 2057f3b..6f5fab4 100644
--- a/connection_manager.h
+++ b/connection_manager.h
@@ -49,6 +49,7 @@
                                NetworkTethering* out_tethering) override;
   bool IsUpdateAllowedOver(NetworkConnectionType type,
                            NetworkTethering tethering) const override;
+  bool IsAllowedConnectionTypesForUpdateSet() const override;
 
  private:
   // Returns (via out_path) the default network path, or empty string if
diff --git a/connection_manager_interface.h b/connection_manager_interface.h
index cb60a3c..2181b5d 100644
--- a/connection_manager_interface.h
+++ b/connection_manager_interface.h
@@ -56,6 +56,10 @@
   virtual bool IsUpdateAllowedOver(NetworkConnectionType type,
                                    NetworkTethering tethering) const = 0;
 
+  // Returns true if the allowed connection types for update is set in the
+  // device policy. Otherwise, returns false.
+  virtual bool IsAllowedConnectionTypesForUpdateSet() const = 0;
+
  protected:
   ConnectionManagerInterface() = default;
 
diff --git a/connection_manager_unittest.cc b/connection_manager_unittest.cc
index 612929b..3e810a7 100644
--- a/connection_manager_unittest.cc
+++ b/connection_manager_unittest.cc
@@ -283,15 +283,23 @@
                                         NetworkTethering::kConfirmed));
 }
 
-TEST_F(ConnectionManagerTest, BlockUpdatesOverCellularByDefaultTest) {
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
+TEST_F(ConnectionManagerTest, AllowUpdatesOverCellularByDefaultTest) {
+  policy::MockDevicePolicy device_policy;
+  // Set an empty device policy.
+  fake_system_state_.set_device_policy(&device_policy);
+
+  EXPECT_TRUE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
                                          NetworkTethering::kUnknown));
 }
 
-TEST_F(ConnectionManagerTest, BlockUpdatesOverTetheredNetworkByDefaultTest) {
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kWifi,
+TEST_F(ConnectionManagerTest, AllowUpdatesOverTetheredNetworkByDefaultTest) {
+  policy::MockDevicePolicy device_policy;
+  // Set an empty device policy.
+  fake_system_state_.set_device_policy(&device_policy);
+
+  EXPECT_TRUE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kWifi,
                                          NetworkTethering::kConfirmed));
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kEthernet,
+  EXPECT_TRUE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kEthernet,
                                          NetworkTethering::kConfirmed));
   EXPECT_TRUE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kWifi,
                                         NetworkTethering::kSuspected));
@@ -320,62 +328,19 @@
                                          NetworkTethering::kUnknown));
 }
 
-TEST_F(ConnectionManagerTest, BlockUpdatesOver3GIfErrorInPolicyFetchTest) {
-  policy::MockDevicePolicy allow_3g_policy;
+TEST_F(ConnectionManagerTest, AllowUpdatesOver3GIfPolicyIsNotSet) {
+  policy::MockDevicePolicy device_policy;
 
-  fake_system_state_.set_device_policy(&allow_3g_policy);
-
-  set<string> allowed_set;
-  allowed_set.insert(
-      cmut_.StringForConnectionType(NetworkConnectionType::kCellular));
+  fake_system_state_.set_device_policy(&device_policy);
 
   // Return false for GetAllowedConnectionTypesForUpdate and see
-  // that updates are still blocked for 3G despite the value being in
-  // the string set above.
-  EXPECT_CALL(allow_3g_policy, GetAllowedConnectionTypesForUpdate(_))
-      .Times(1)
-      .WillOnce(DoAll(SetArgPointee<0>(allowed_set), Return(false)));
-
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
-                                         NetworkTethering::kUnknown));
-}
-
-TEST_F(ConnectionManagerTest, UseUserPrefForUpdatesOverCellularIfNoPolicyTest) {
-  policy::MockDevicePolicy no_policy;
-  testing::NiceMock<MockPrefs>* prefs = fake_system_state_.mock_prefs();
-
-  fake_system_state_.set_device_policy(&no_policy);
-
-  // No setting enforced by the device policy, user prefs should be used.
-  EXPECT_CALL(no_policy, GetAllowedConnectionTypesForUpdate(_))
-      .Times(3)
-      .WillRepeatedly(Return(false));
-
-  // No user pref: block.
-  EXPECT_CALL(*prefs, Exists(kPrefsUpdateOverCellularPermission))
+  // that updates are allowed as device policy is not set. Further
+  // check is left to |OmahaRequestAction|.
+  EXPECT_CALL(device_policy, GetAllowedConnectionTypesForUpdate(_))
       .Times(1)
       .WillOnce(Return(false));
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
-                                         NetworkTethering::kUnknown));
 
-  // Allow per user pref.
-  EXPECT_CALL(*prefs, Exists(kPrefsUpdateOverCellularPermission))
-      .Times(1)
-      .WillOnce(Return(true));
-  EXPECT_CALL(*prefs, GetBoolean(kPrefsUpdateOverCellularPermission, _))
-      .Times(1)
-      .WillOnce(DoAll(SetArgPointee<1>(true), Return(true)));
   EXPECT_TRUE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
-                                        NetworkTethering::kUnknown));
-
-  // Block per user pref.
-  EXPECT_CALL(*prefs, Exists(kPrefsUpdateOverCellularPermission))
-      .Times(1)
-      .WillOnce(Return(true));
-  EXPECT_CALL(*prefs, GetBoolean(kPrefsUpdateOverCellularPermission, _))
-      .Times(1)
-      .WillOnce(DoAll(SetArgPointee<1>(false), Return(true)));
-  EXPECT_FALSE(cmut_.IsUpdateAllowedOver(NetworkConnectionType::kCellular,
                                          NetworkTethering::kUnknown));
 }
 
diff --git a/dbus_bindings/org.chromium.UpdateEngineInterface.dbus-xml b/dbus_bindings/org.chromium.UpdateEngineInterface.dbus-xml
index 848f775..a20f33f 100644
--- a/dbus_bindings/org.chromium.UpdateEngineInterface.dbus-xml
+++ b/dbus_bindings/org.chromium.UpdateEngineInterface.dbus-xml
@@ -67,6 +67,10 @@
     <method name="SetUpdateOverCellularPermission">
       <arg type="b" name="allowed" direction="in" />
     </method>
+    <method name="SetUpdateOverCellularTarget">
+      <arg type="s" name="target_version" direction="in" />
+      <arg type="x" name="target_size" direction="in" />
+    </method>
     <method name="GetUpdateOverCellularPermission">
       <arg type="b" name="allowed" direction="out" />
     </method>
diff --git a/dbus_service.cc b/dbus_service.cc
index 18b5b9e..e64481b 100644
--- a/dbus_service.cc
+++ b/dbus_service.cc
@@ -122,6 +122,14 @@
   return common_->SetUpdateOverCellularPermission(error, in_allowed);
 }
 
+bool DBusUpdateEngineService::SetUpdateOverCellularTarget(
+    brillo::ErrorPtr* error,
+    const std::string& target_version,
+    int64_t target_size) {
+  return common_->SetUpdateOverCellularTarget(error, target_version,
+                                              target_size);
+}
+
 bool DBusUpdateEngineService::GetUpdateOverCellularPermission(
     ErrorPtr* error, bool* out_allowed) {
   return common_->GetUpdateOverCellularPermission(error, out_allowed);
diff --git a/dbus_service.h b/dbus_service.h
index 0b63492..efad821 100644
--- a/dbus_service.h
+++ b/dbus_service.h
@@ -114,6 +114,12 @@
   bool SetUpdateOverCellularPermission(brillo::ErrorPtr* error,
                                        bool in_allowed) override;
 
+  // If there's no device policy installed, sets the update over cellular
+  // target. Otherwise, this method returns with an error.
+  bool SetUpdateOverCellularTarget(brillo::ErrorPtr* error,
+                                   const std::string& target_version,
+                                   int64_t target_size) override;
+
   // Returns the current value of the update over cellular network setting,
   // either forced by the device policy if the device is enrolled or the current
   // user preference otherwise.
diff --git a/metrics_utils.cc b/metrics_utils.cc
index e165e89..4f26758 100644
--- a/metrics_utils.cc
+++ b/metrics_utils.cc
@@ -109,6 +109,7 @@
     case ErrorCode::kPostinstallPowerwashError:
     case ErrorCode::kUpdateCanceledByChannelChange:
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
+    case ErrorCode::kOmahaUpdateIgnoredOverCellular:
       return metrics::AttemptResult::kInternalError;
 
     // Special flags. These can't happen (we mask them out above) but
@@ -209,6 +210,7 @@
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
+    case ErrorCode::kOmahaUpdateIgnoredOverCellular:
       break;
 
     // Special flags. These can't happen (we mask them out above) but
diff --git a/mock_connection_manager.h b/mock_connection_manager.h
index 109c529..c0745b7 100644
--- a/mock_connection_manager.h
+++ b/mock_connection_manager.h
@@ -36,6 +36,7 @@
 
   MOCK_CONST_METHOD2(IsUpdateAllowedOver, bool(NetworkConnectionType type,
                                                NetworkTethering tethering));
+  MOCK_CONST_METHOD0(IsAllowedConnectionTypesForUpdateSet, bool());
 };
 
 }  // namespace chromeos_update_engine
diff --git a/omaha_request_action.cc b/omaha_request_action.cc
index 173d387..fb258c2 100644
--- a/omaha_request_action.cc
+++ b/omaha_request_action.cc
@@ -980,9 +980,11 @@
   output_object.update_exists = true;
   SetOutputObject(output_object);
 
-  if (ShouldIgnoreUpdate(output_object)) {
-    output_object.update_exists = false;
-    completer.set_code(ErrorCode::kOmahaUpdateIgnoredPerPolicy);
+  ErrorCode error = ErrorCode::kSuccess;
+  if (ShouldIgnoreUpdate(&error, output_object)) {
+    // No need to change output_object.update_exists here, since the value
+    // has been output to the pipe.
+    completer.set_code(error);
     return;
   }
 
@@ -1439,6 +1441,7 @@
     break;
 
   case ErrorCode::kOmahaUpdateIgnoredPerPolicy:
+  case ErrorCode::kOmahaUpdateIgnoredOverCellular:
     result = metrics::CheckResult::kUpdateAvailable;
     reaction = metrics::CheckReaction::kIgnored;
     break;
@@ -1473,7 +1476,7 @@
 }
 
 bool OmahaRequestAction::ShouldIgnoreUpdate(
-    const OmahaResponse& response) const {
+    ErrorCode* error, const OmahaResponse& response) const {
   // Note: policy decision to not update to a version we rolled back from.
   string rollback_version =
       system_state_->payload_state()->GetRollbackVersion();
@@ -1481,11 +1484,12 @@
     LOG(INFO) << "Detected previous rollback from version " << rollback_version;
     if (rollback_version == response.version) {
       LOG(INFO) << "Received version that we rolled back from. Ignoring.";
+      *error = ErrorCode::kOmahaUpdateIgnoredPerPolicy;
       return true;
     }
   }
 
-  if (!IsUpdateAllowedOverCurrentConnection()) {
+  if (!IsUpdateAllowedOverCurrentConnection(error, response)) {
     LOG(INFO) << "Update is not allowed over current connection.";
     return true;
   }
@@ -1500,7 +1504,59 @@
   return false;
 }
 
-bool OmahaRequestAction::IsUpdateAllowedOverCurrentConnection() const {
+bool OmahaRequestAction::IsUpdateAllowedOverCellularByPrefs(
+    const OmahaResponse& response) const {
+  PrefsInterface* prefs = system_state_->prefs();
+
+  if (!prefs) {
+    LOG(INFO) << "Disabling updates over cellular as the preferences are "
+                 "not available.";
+    return false;
+  }
+
+  bool is_allowed;
+
+  if (prefs->Exists(kPrefsUpdateOverCellularPermission) &&
+      prefs->GetBoolean(kPrefsUpdateOverCellularPermission, &is_allowed) &&
+      is_allowed) {
+    LOG(INFO) << "Allowing updates over cellular as permission preference is "
+                 "set to true.";
+    return true;
+  }
+
+  if (!prefs->Exists(kPrefsUpdateOverCellularTargetVersion) ||
+      !prefs->Exists(kPrefsUpdateOverCellularTargetSize)) {
+    LOG(INFO) << "Disabling updates over cellular as permission preference is "
+                 "set to false or does not exist while target does not exist.";
+    return false;
+  }
+
+  std::string target_version;
+  int64_t target_size;
+
+  if (!prefs->GetString(kPrefsUpdateOverCellularTargetVersion,
+                        &target_version) ||
+      !prefs->GetInt64(kPrefsUpdateOverCellularTargetSize,
+                       &target_size)) {
+    LOG(INFO) << "Disabling updates over cellular as the target version or "
+                 "size is not accessible.";
+    return false;
+  }
+
+  if (target_version == response.version && target_size == response.size) {
+    LOG(INFO) << "Allowing updates over cellular as the target matches the"
+                 "omaha response.";
+    return true;
+  } else {
+    LOG(INFO) << "Disabling updates over cellular as the target does not"
+                 "match the omaha response.";
+    return false;
+  }
+}
+
+bool OmahaRequestAction::IsUpdateAllowedOverCurrentConnection(
+    ErrorCode* error,
+    const OmahaResponse& response) const {
   NetworkConnectionType type;
   NetworkTethering tethering;
   ConnectionManagerInterface* connection_manager =
@@ -1510,7 +1566,30 @@
               << "Defaulting to allow updates.";
     return true;
   }
+
   bool is_allowed = connection_manager->IsUpdateAllowedOver(type, tethering);
+  bool is_device_policy_set = connection_manager->
+                                  IsAllowedConnectionTypesForUpdateSet();
+  // Treats tethered connection as if it is cellular connection.
+  bool is_over_cellular = type == NetworkConnectionType::kCellular ||
+                          tethering == NetworkTethering::kConfirmed;
+
+  if (!is_over_cellular) {
+    // There's no need to further check user preferences as we are not over
+    // cellular connection.
+    if (!is_allowed)
+      *error = ErrorCode::kOmahaUpdateIgnoredPerPolicy;
+  } else if (is_device_policy_set) {
+    // There's no need to further check user preferences as the device policy
+    // is set regarding updates over cellular.
+    if (!is_allowed)
+      *error = ErrorCode::kOmahaUpdateIgnoredPerPolicy;
+  } else if (!IsUpdateAllowedOverCellularByPrefs(response)) {
+    // The user prefereces does not allow updates over cellular.
+    is_allowed = false;
+    *error = ErrorCode::kOmahaUpdateIgnoredOverCellular;
+  }
+
   LOG(INFO) << "We are connected via "
             << ConnectionManager::StringForConnectionType(type)
             << ", Updates allowed: " << (is_allowed ? "Yes" : "No");
diff --git a/omaha_request_action.h b/omaha_request_action.h
index 2915a6a..7d35c23 100644
--- a/omaha_request_action.h
+++ b/omaha_request_action.h
@@ -299,11 +299,17 @@
   void OnLookupPayloadViaP2PCompleted(const std::string& url);
 
   // Returns true if the current update should be ignored.
-  bool ShouldIgnoreUpdate(const OmahaResponse& response) const;
+  bool ShouldIgnoreUpdate(ErrorCode* error,
+                          const OmahaResponse& response) const;
+
+  // Return true if updates are allowed by user preferences.
+  bool IsUpdateAllowedOverCellularByPrefs(const OmahaResponse& response) const;
 
   // Returns true if updates are allowed over the current type of connection.
   // False otherwise.
-  bool IsUpdateAllowedOverCurrentConnection() const;
+  bool IsUpdateAllowedOverCurrentConnection(
+      ErrorCode* error,
+      const OmahaResponse& response) const;
 
   // Global system context.
   SystemState* system_state_;
diff --git a/omaha_request_action_unittest.cc b/omaha_request_action_unittest.cc
index d4b166f..6c24f86 100644
--- a/omaha_request_action_unittest.cc
+++ b/omaha_request_action_unittest.cc
@@ -487,6 +487,185 @@
   EXPECT_FALSE(response.update_exists);
 }
 
+TEST_F(OmahaRequestActionTest, ValidUpdateOverCellularAllowedByDevicePolicy) {
+  // This test tests that update over cellular is allowed as device policy
+  // says yes.
+  OmahaResponse response;
+  MockConnectionManager mock_cm;
+
+  fake_system_state_.set_connection_manager(&mock_cm);
+
+  EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
+      .WillRepeatedly(
+          DoAll(SetArgumentPointee<0>(NetworkConnectionType::kCellular),
+                SetArgumentPointee<1>(NetworkTethering::kUnknown),
+                Return(true)));
+  EXPECT_CALL(mock_cm, IsAllowedConnectionTypesForUpdateSet())
+      .WillRepeatedly(Return(true));
+  EXPECT_CALL(mock_cm, IsUpdateAllowedOver(NetworkConnectionType::kCellular, _))
+      .WillRepeatedly(Return(true));
+
+  ASSERT_TRUE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kSuccess,
+                      metrics::CheckResult::kUpdateAvailable,
+                      metrics::CheckReaction::kUpdating,
+                      metrics::DownloadErrorCode::kUnset,
+                      &response,
+                      nullptr));
+  EXPECT_TRUE(response.update_exists);
+}
+
+TEST_F(OmahaRequestActionTest, ValidUpdateOverCellularBlockedByDevicePolicy) {
+  // This test tests that update over cellular is blocked as device policy
+  // says no.
+  OmahaResponse response;
+  MockConnectionManager mock_cm;
+
+  fake_system_state_.set_connection_manager(&mock_cm);
+
+  EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
+      .WillRepeatedly(
+          DoAll(SetArgumentPointee<0>(NetworkConnectionType::kCellular),
+                SetArgumentPointee<1>(NetworkTethering::kUnknown),
+                Return(true)));
+  EXPECT_CALL(mock_cm, IsAllowedConnectionTypesForUpdateSet())
+      .WillRepeatedly(Return(true));
+  EXPECT_CALL(mock_cm, IsUpdateAllowedOver(NetworkConnectionType::kCellular, _))
+      .WillRepeatedly(Return(false));
+
+  ASSERT_FALSE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kOmahaUpdateIgnoredPerPolicy,
+                      metrics::CheckResult::kUpdateAvailable,
+                      metrics::CheckReaction::kIgnored,
+                      metrics::DownloadErrorCode::kUnset,
+                      &response,
+                      nullptr));
+  EXPECT_FALSE(response.update_exists);
+}
+
+TEST_F(OmahaRequestActionTest,
+       ValidUpdateOverCellularAllowedByUserPermissionTrue) {
+  // This test tests that, when device policy is not set, update over cellular
+  // is allowed as permission for update over cellular is set to true.
+  OmahaResponse response;
+  MockConnectionManager mock_cm;
+
+  fake_prefs_.SetBoolean(kPrefsUpdateOverCellularPermission, true);
+  fake_system_state_.set_connection_manager(&mock_cm);
+
+  EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
+      .WillRepeatedly(
+          DoAll(SetArgumentPointee<0>(NetworkConnectionType::kCellular),
+                SetArgumentPointee<1>(NetworkTethering::kUnknown),
+                Return(true)));
+  EXPECT_CALL(mock_cm, IsAllowedConnectionTypesForUpdateSet())
+      .WillRepeatedly(Return(false));
+  EXPECT_CALL(mock_cm, IsUpdateAllowedOver(NetworkConnectionType::kCellular, _))
+      .WillRepeatedly(Return(true));
+
+  ASSERT_TRUE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kSuccess,
+                      metrics::CheckResult::kUpdateAvailable,
+                      metrics::CheckReaction::kUpdating,
+                      metrics::DownloadErrorCode::kUnset,
+                      &response,
+                      nullptr));
+  EXPECT_TRUE(response.update_exists);
+}
+
+TEST_F(OmahaRequestActionTest,
+       ValidUpdateOverCellularBlockedByUpdateTargetNotMatch) {
+  // This test tests that, when device policy is not set and permission for
+  // update over cellular is set to false or does not exist, update over
+  // cellular is blocked as update target does not match the omaha response.
+  OmahaResponse response;
+  MockConnectionManager mock_cm;
+  // A version different from the version in omaha response.
+  string diff_version = "99.99.99";
+  // A size different from the size in omaha response.
+  int64_t diff_size = 999;
+
+  fake_prefs_.SetString(kPrefsUpdateOverCellularTargetVersion, diff_version);
+  fake_prefs_.SetInt64(kPrefsUpdateOverCellularTargetSize, diff_size);
+  // This test tests cellular (3G) being the only connection type being allowed.
+  fake_system_state_.set_connection_manager(&mock_cm);
+
+  EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
+      .WillRepeatedly(
+          DoAll(SetArgumentPointee<0>(NetworkConnectionType::kCellular),
+                SetArgumentPointee<1>(NetworkTethering::kUnknown),
+                Return(true)));
+  EXPECT_CALL(mock_cm, IsAllowedConnectionTypesForUpdateSet())
+      .WillRepeatedly(Return(false));
+  EXPECT_CALL(mock_cm, IsUpdateAllowedOver(NetworkConnectionType::kCellular, _))
+      .WillRepeatedly(Return(true));
+
+  ASSERT_FALSE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kOmahaUpdateIgnoredOverCellular,
+                      metrics::CheckResult::kUpdateAvailable,
+                      metrics::CheckReaction::kIgnored,
+                      metrics::DownloadErrorCode::kUnset,
+                      &response,
+                      nullptr));
+  EXPECT_FALSE(response.update_exists);
+}
+
+TEST_F(OmahaRequestActionTest,
+       ValidUpdateOverCellularAllowedByUpdateTargetMatch) {
+  // This test tests that, when device policy is not set and permission for
+  // update over cellular is set to false or does not exist, update over
+  // cellular is allowed as update target matches the omaha response.
+  OmahaResponse response;
+  MockConnectionManager mock_cm;
+  // A version same as the version in omaha response.
+  string new_version = fake_update_response_.version;
+  // A size same as the size in omaha response.
+  int64_t new_size = fake_update_response_.size;
+
+  fake_prefs_.SetString(kPrefsUpdateOverCellularTargetVersion, new_version);
+  fake_prefs_.SetInt64(kPrefsUpdateOverCellularTargetSize, new_size);
+  fake_system_state_.set_connection_manager(&mock_cm);
+
+  EXPECT_CALL(mock_cm, GetConnectionProperties(_, _))
+      .WillRepeatedly(
+          DoAll(SetArgumentPointee<0>(NetworkConnectionType::kCellular),
+                SetArgumentPointee<1>(NetworkTethering::kUnknown),
+                Return(true)));
+  EXPECT_CALL(mock_cm, IsAllowedConnectionTypesForUpdateSet())
+      .WillRepeatedly(Return(false));
+  EXPECT_CALL(mock_cm, IsUpdateAllowedOver(NetworkConnectionType::kCellular, _))
+      .WillRepeatedly(Return(true));
+
+  ASSERT_TRUE(
+      TestUpdateCheck(nullptr,  // request_params
+                      fake_update_response_.GetUpdateResponse(),
+                      -1,
+                      false,  // ping_only
+                      ErrorCode::kSuccess,
+                      metrics::CheckResult::kUpdateAvailable,
+                      metrics::CheckReaction::kUpdating,
+                      metrics::DownloadErrorCode::kUnset,
+                      &response,
+                      nullptr));
+  EXPECT_TRUE(response.update_exists);
+}
+
 TEST_F(OmahaRequestActionTest, ValidUpdateBlockedByRollback) {
   string rollback_version = "1234.0.0";
   OmahaResponse response;
diff --git a/payload_state.cc b/payload_state.cc
index af1ad05..72f7646 100644
--- a/payload_state.cc
+++ b/payload_state.cc
@@ -347,6 +347,7 @@
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
+    case ErrorCode::kOmahaUpdateIgnoredOverCellular:
       LOG(INFO) << "Not incrementing URL index or failure count for this error";
       break;
 
diff --git a/update_attempter.cc b/update_attempter.cc
index a7b6ef0..55ef948 100644
--- a/update_attempter.cc
+++ b/update_attempter.cc
@@ -52,6 +52,7 @@
 #include "update_engine/common/prefs_interface.h"
 #include "update_engine/common/subprocess.h"
 #include "update_engine/common/utils.h"
+#include "update_engine/connection_manager.h"
 #include "update_engine/dbus_service.h"
 #include "update_engine/metrics.h"
 #include "update_engine/omaha_request_action.h"
@@ -1017,9 +1018,20 @@
         consecutive_failed_update_checks_ = 0;
       }
 
+      const OmahaResponse& omaha_response =
+          omaha_request_action->GetOutputObject();
       // Store the server-dictated poll interval, if any.
       server_dictated_poll_interval_ =
-          std::max(0, omaha_request_action->GetOutputObject().poll_interval);
+          std::max(0, omaha_response.poll_interval);
+
+      // This update is ignored by omaha request action because update over
+      // cellular connection is not allowed. Needs to ask for user's permissions
+      // to update.
+      if (code == ErrorCode::kOmahaUpdateIgnoredOverCellular) {
+        new_version_ = omaha_response.version;
+        new_payload_size_ = omaha_response.size;
+        SetStatusAndNotify(UpdateStatus::NEED_PERMISSION_TO_UPDATE);
+      }
     }
   }
   if (code != ErrorCode::kSuccess) {
diff --git a/update_manager/chromeos_policy.cc b/update_manager/chromeos_policy.cc
index 27f0304..e1fe398 100644
--- a/update_manager/chromeos_policy.cc
+++ b/update_manager/chromeos_policy.cc
@@ -132,6 +132,7 @@
     case ErrorCode::kOmahaRequestXMLHasEntityDecl:
     case ErrorCode::kFilesystemVerifierError:
     case ErrorCode::kUserCanceled:
+    case ErrorCode::kOmahaUpdateIgnoredOverCellular:
       LOG(INFO) << "Not changing URL index or failure count due to error "
                 << chromeos_update_engine::utils::ErrorCodeToString(err_code)
                 << " (" << static_cast<int>(err_code) << ")";
diff --git a/update_status_utils.cc b/update_status_utils.cc
index 9685853..1b2dfbc 100644
--- a/update_status_utils.cc
+++ b/update_status_utils.cc
@@ -25,6 +25,7 @@
 const char kWeaveStatusIdle[] = "idle";
 const char kWeaveStatusCheckingForUpdate[] = "checkingForUpdate";
 const char kWeaveStatusUpdateAvailable[] = "updateAvailable";
+const char kWeaveStatusNeedPermissionToUpdate[] = "needPermissionToUpdate";
 const char kWeaveStatusDownloading[] = "downloading";
 const char kWeaveStatusVerifying[] = "verifying";
 const char kWeaveStatusFinalizing[] = "finalizing";
@@ -45,6 +46,8 @@
       return update_engine::kUpdateStatusCheckingForUpdate;
     case UpdateStatus::UPDATE_AVAILABLE:
       return update_engine::kUpdateStatusUpdateAvailable;
+    case UpdateStatus::NEED_PERMISSION_TO_UPDATE:
+      return update_engine::kUpdateStatusNeedPermissionToUpdate;
     case UpdateStatus::DOWNLOADING:
       return update_engine::kUpdateStatusDownloading;
     case UpdateStatus::VERIFYING:
@@ -73,6 +76,8 @@
       return kWeaveStatusCheckingForUpdate;
     case UpdateStatus::UPDATE_AVAILABLE:
       return kWeaveStatusUpdateAvailable;
+    case UpdateStatus::NEED_PERMISSION_TO_UPDATE:
+      return kWeaveStatusNeedPermissionToUpdate;
     case UpdateStatus::DOWNLOADING:
       return kWeaveStatusDownloading;
     case UpdateStatus::VERIFYING:
@@ -104,6 +109,9 @@
   } else if (s == update_engine::kUpdateStatusUpdateAvailable) {
     *status = UpdateStatus::UPDATE_AVAILABLE;
     return true;
+  } else if (s == update_engine::kUpdateStatusNeedPermissionToUpdate) {
+    *status = UpdateStatus::NEED_PERMISSION_TO_UPDATE;
+    return true;
   } else if (s == update_engine::kUpdateStatusDownloading) {
     *status = UpdateStatus::DOWNLOADING;
     return true;